Cerebral aneurysms may develop when a weakened area of a blood vessel (e.g., a blood vessel in or around the brain) bulges outward. If not treated, aneurysms can rupture resulting in hemorrhagic stroke, a major cause of mortality and long-term disability. Taking cerebral aneurysms for example, there are several modalities used to treat cerebral aneurysms including: (1) traditional surgical clipping, and (2) endovascular embolization. Surgical clipping is a traumatic procedure that involves craniotomy, retraction of the brain to expose the aneurysm, and placement of a metal clip across the aneurysm neck. Endovascular embolization is a minimally invasive technique in which embolic agents are delivered into the aneurysm via a catheter, under fluoroscopic (x-ray) guidance, to occlude the aneurysm and promote healing.
Regarding endovascular embolization, the Gugliemi Detachable Coil (GDC) allows a surgeon to deploy a helical platinum coil into the aneurysm. Once in proper position, the coil is detached from the delivery apparatus and released into the aneurysm. Multiple coils may be required to effectively fill the aneurysm and induce clotting and eventual sealing of the aneurysm from the parent vessel. Such coils are subject to problematic issues with recanalization and related insufficient healing.
Though not as prevalent as embolic coils, liquid embolic agents that solidify inside the aneurysm are also available for clinical use in rare cases. However, such agents can be difficult to precisely administer at specific sites.